That's right, it will not affect the install. I know a lot of people keep saying to access from the top, but I'm thinking you will have better access from the bottom, with the reinforcement plate removed but it is the most difficult sensor to access for sure.

Bumping up this thread... Doing both my precat O2 sensors, I removed the egr valve and have the heat shield above the headers loose, but I can't get it out. It seems impossible without disconnecting this coolant line:

Can anyone tell me how they got their heat shield off? And if I have to disconnect the coolant line, is all of my coolant in the reservoir going to drain out?? That would be a pita

Edit:

After taking off the lower skid plate I realized that with my sgt headers all four oxygen sensors are pretty easily accessible under the car. Looks like I didn't need to loosen the heat shield in the first place!

BTB, why are you removing things? I just changed my pre cat o2s with a crow's foot and the only thing I did besides jacking the car up was removing the valve beauty cover to expose the harnesses for the O2s.

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